Analogue – digital display: A watch that shows the time by means of hour and minute hands (analogue display) as well as by numbers (a digital display).

Analogue: A watch that shows the time using hour and minute hands.

Anti-magnetic: The movement of a mechanical watch can be thrown off balance if it comes in contact with a strong magnetic field; Magnetism is common in loudspeakers, televisions, refrigerators, cars, etc. etc. and these days most watches claim to be anti-magnetic. This is achieved by using alloys for certain parts, among them the balance wheel and escape wheel. Electronic watches are not susceptible to magnetism.

Automatic winding: (or self-winding) This term refers to a watch with a mechanical movement (as opposed to a quartz or electrical movement). The watch is wound by the motion of the wearer’s arm rather than through turning the winding stem. A rotor that turns in response to motion winds the watch’s mainspring. If an automatic watch is not worn for a day or two, it will wind down and need to be wound by hand to get it started again.

Balance: This is essentially and oscillator which regulates the speed of the movement of a mechanical watch.

Bar – A small rod used to fix a watch band to the body of the watch.

Battery reserve indicator (or end of battery indicator): Some battery operated watches have a feature that indicates when the battery is approaching the end of its life. This is often indicated by the second hand moving in two second intervals instead of each second.

Bezel: The ring which surrounds the watch dial (or face). The bezel is usually made of gold, gold plate or stainless steel.

Bi-directional rotating bezel: A bezel that can be rotated either clockwise or counter clockwise. These are used for mathematical calculations such as average speed or distance (see “slide rule”) or for keeping track of elapsed time(see “elapsed time rotating bezel”).

Bombe – convex French

Bracelet – A metal watchband, available in many types of alloy, from stainless steel to gold.

Butterfly Clasp – See Deployant Clasp. A clip which opens in two directions expanding to enable easier putting on and removal of a wristwatch.

Built-in illumination: Lighting on a watch dial that allows the wearer to read the time in the dark. Check out Seiko’s Lumi-brite technology.

Sapphire – Man made sapphire crystal used for its hardness and scratch resistant qualities in watch making.

Sapphire crystal: A crystal made of synthetic sapphire, a transparent, shatter-resistant, scratch-resistant substance.

Screw-lock crown: A crown that can be screwed into the case to make the watch watertight.

Screw-down crown: The crown of a watch that screws on / in to the case to better seal the watch. This ensures more water and dust resistance.

Second time-zone indicator: An additional dial that can be set to the time in another time zone. It lets the wearer keep track of local time and the time in another country simultaneously.

Shock resistance: As defined by U.S. government regulation, a watch’s ability to withstand an impact equal to that of being dropped onto a wood floor from a height of 3 feet.

Skeleton watch: A watch with no dial and only a chapter ring. As much metal is removed as possible and all the remaining parts are decorated with elaborate engravings.

Slide rule: A device, consisting of logarithmic or other scales on the outer edge of the watch face, that can be used to do mathematical calculations. One of the scales is marked on a rotating bezel, which can be slid against the stationary scale to make the calculations. Some watches have slide rules that allow specific calculations, such as for fuel consumption by an airplane or fuel weight.

Solar powered: A watch that uses solar energy (from any light source) to power the quartz movement. The Citizen >Solar-Tech<>itizens Internet Site.

Spring bars (or pins) : Spring-loaded bars between the lugs on the case, used to attach a strap or metal bracelet to the case.

Stepping motor: The part of a quartz movement that moves the gear train, which in turn moves the watch’s hands.

Stopwatch: A watch with a seconds hand that measures intervals of time. When a stopwatch is incorporated into a standard watch, both the stopwatch function and the timepiece are referred to as a chronograph.

Sub-dial: A small dial on a watch face used for any of several purposes, such as keeping track of elapsed minutes or hours on a chronograph or indicating the date.

Swiss made: As a part of a move towards greater consumer protection and in order to combat fakes in the Far East that claim to be Swiss made, the Swiss federal council in 1993 laid down the rule that a watch has to satisfy before it could be described as Swiss made. The movement must be of Swiss origin, and must contain at least 50% Swiss parts. The watch must be cased in Switzerland and pass its final inspection in that country.

Calendar: A feature that shows the date, and often the day of the week. There are several types of calendar watches. Most calendar watches show the information digitally through an aperture on the watch face. Some chronograph watches shoe the information on sub-dials on the watch face.

Calibre – Has a number of meanings within horological circles. It can refer to the size of a watch movement. Most often used to referring to the model or series of movement within the catalogue of a particular manufacturer. A Calibre may have meanings such as type of movement, series, period of manufacture etc within the one number.

Case / caseback: The case of a watch must not only protect the mechanism and hold all the parts together but it must also look good -sometimes to the extent of making a timepiece into a piece of jewellery. A watch case is generally in 3 parts -the bezel, which holds the crystal, -the band or centre part, which contains the movement, -and the back, either snapped or screwed on, in to which, sometimes, is fitted a crystal so that an intricate mechanical movement watch.

Case materials: Materials range from inexpensive cast metal through moulded plastic to solid chunks of steel or gold from which the case is machined. In Great Britain, gold cases are usually 18k, but less expensive watches are 9k. In most other countries, 14k is preferred. Caratage indicates the gold content of metal, stated as the number of parts of gold in every 24 parts, i.e. 18k gold is 18 parts of gold alloyed with six parts of metal. Platinum is becoming increasingly popular, as is titanium for its lightness. Ceramic cases and bracelets -a scratch resistant space age material formed under great pressure and heat from powder -are used by some manufacturers. It does not bear any resemblance to the ceramics used in pottery. Some watches in the middle price ranges are gold plated over brass -9k or 18k plating usually. Vermeil is the term used to describe silver which has been gold plated.

Centre seconds: Seconds indicated by a hand at the centre of the dial, along with the hour and minute hands.

Chapter ring: The ring on the watch dial bearing figures and minute marks. The hour figures are sometimes called chapters.

Chronograph: A watch that includes a built in stopwatch function – i.e., a timer that can be started and stopped to time an event. There are many variations on the chronograph. Some operate with a center seconds hand which keeps time on the watch’s main dial. Others use sub-dials to time elapsed hours, minutes and seconds. Still others show elapsed time on a digital display on the watch face. Some chronographs can be used as a lap timer (see “fly back hand” and “split seconds hand”). The accuracy of the stopwatch function will commonly vary from 1/5th second to 1/100th second depending on the chronograph. Some chronographs will measure elapsed time up to 24 hours. Watches that include the chronograph function are themselves called “chronographs.” When a chronograph is used in conjunction with specialized scales on the watch face it can perform many different functions, such as determining speed or distance (see “tachymeter” and “telemeter”) Do not confuse the term “chronograph” with “chronometer.” The latter refers to a timepiece, which may or may not have a chronograph function, which has met certain high standards of accuracy set by an official watch institute in Switzerland.

Chronometer: Technically speaking, all watches are chronometers. But for a Swiss made watch to be called a chronometer, it must meet certain very high standards set by the Swiss Official Chronometer Control (C.O.S.C.). If you have a Swiss watch labelled as a chronometer, you can be certain that it has a mechanical movement of the very highest quality.

Co-Axial: The configuration of having two hands running on the same axis.
Complications: One or more features added to a watch in addition to its usual time-telling functions, which normally not only include the hours, minutes and seconds but also date and often the day of the week as well. Complications such as; perpetual calendars, moon phase displays, alarms, repeating mechanisms, quarter strikes as well as stop/start chronograph functions. Power reserve indicators are also usually regarded as ‘complications’
Contrôle Officiel Suisse des Chronomètres – The official Swiss Chronometer testing institute that verifies a watch’s accuracy.

Côtes de Genève – Machined oscillating pattern on the flat surfaces of a watch movement.

Cosmograph: The Cosmograph differs to the chronograph in that the tachymeter is on the bezel rather than on the outer rim of the dial. This was invented by Rolex to create a more modern look to the watch.

Countdown timer: A function that lets the wearer keep track of how much of a pre-set period of time has elapsed. Some countdown timers sound a warning signal a few seconds before the time runs out. These are useful in events such as yacht races, where the sailor must manoeuvre the boat into position before the start of a race.

Crown: Also called a stem or pin, a crown is the button on the outside of the watch case that is used to set the time and date. In a mechanical watch the crown also winds the mainspring. In this case it is also called a “winding stem”. A screw in (or screw down) crown is used to make a watch more water resistant. The crown actually screws into the case, dramatically increasing the water-tightness of the watch.

Crystal: The transparent cover on a watch face made of glass crystal, synthetic sapphire or plastic. Better watches often have a sapphire crystal which is highly resistant to scratching or shattering.

Sapphire Crystals – Most often found on high end watches, all but scratchproof. However Sapphire crystal is subject to shattering under strong localized impacts.

Acrylic – Resistant to small knocks and scratching. It can be polished to restore clarity and appearance.

Mineral Glass: Glass hardened by a process of heat treatment. Approximately 10 times harder than acrylic, mineral glass is extremely scratch resistant but must be replaced if it is scratched.

Cyclops: Rolex term for a small lens in the glass/crystal used to magnify date elements on the face of a watch.

Deployant: A type of buckle attached to the band or bracelet of a watch consisting of several hinged parts that open and expand to more easily put on and take off the watch.

Depth alarm: An alarm on a divers’ watch that sounds when the wearer exceeds a pre-set depth.

Depth sensor/depth meter: A device on a divers’ watch that determines the wearer’s depth by measuring water pressure. It shows the depth either by analogue hands and a scale on the watch face or through a digital display.

Dial: The watch face.

Digital watch: A watch that shows the time through digits rather than through a dial and hands (analogue) display.
Display back – An open back watch casing that allows the movement of the watch to be viewed easily.

Dual Time -Zone A watch that is capable, by means including several hour hands on the one face or several dials on the one face, of displaying more than one time zone at once eg The Rolex GMT Master 2 can show one time on its main face and another time can be independently set on the 24 hour hand.

ETA: Swiss manufacturer of mechanical movements. Although held in the highest regard, their movements are available in watches retailing under $1000 up to tens of thousands.

Elapsed time rotating bezel: A graduated rotating bezel (see rotating bezel”) used to keep track of elapsed time. The bezel can be turned so the wearer can align the zero on the bezel with the watch’s seconds or minutes hand. After a period of time passes, you can read the elapsed time off the bezel. This saves you having to perform the subtraction that would be necessary if you used the watch’s regular dial.

Electronic (quartz) watch: A watch, usually battery-powered, which uses an electric current to cause a quartz oscillator to vibrate, normally 32,768 Hz per second but sometimes at much higher frequencies. These vibrations are processed by an integrated circuit which transforms the current into impulses. These are fed into a stepping motor which drives a train of gears to move the hands. Some quartz watches have solar cells which take light from any soul, natural or artificial, and transform them into electrical energy. Another form is the Seiko Kinetic (See Kinetic).

Escapement: Device in a mechanical movement that controls the rotation of the wheels and thus the motion of the hands.

Flinqué – The use of engraving on the surface of a watch, then covered with enamel to form a decorative surface.

Flyback hand: A seconds hand on a chronograph that can be used to time laps or to determine finishing times for several competitors in a race. Start the chronograph, putting both the fly back hand and the regular chronograph seconds hand in motion. To record a lap time or finishing time, stop the fly back hand. After recording time, push a button till the hand “flies back” to catch up with the constantly moving elapsed-time hand. Repeat the process to record as many lap times or finishing times as needed.

Gear train: The system of gears which transmits power from the mainspring to the escapement.

GMT – Abbreviation for Greenwich Mean Time. As a feature of watches, it means that two or more time zones are displayed.

Gold plated: A layer of gold electroplated to a base metal.

Guilloché – Curved lines interlaced to form a patterned surface.

Grande complications: The most complex of mechanical watches featuring an abundance of complications. The term is normally restricted to mechanical watches. Quartz watches with additional features are usually described as ‘multi-functional’.

Hand – Moving part of the face of a watch which indicates on the dial values such as hour, minute, date etc.

Helium escape valve – Divers watches are often fitted with a HEV. Air with a higher helium component is used in diving applications conducted at great depths. Helium, having a smaller molecular size than other air elements, can move in and out of a watch casing regardless of seal. When depressurizing, either in open water or even pressurized cabin helium can become trapped inside the casing, blow out the glass/crystal and damage components. A helium escape valve allows one way movement of expanding helium to escape the casing.

Kinetic: Refers to the Seiko line of Kinetic watches. This innovative technology has a quartz movement that does not use a battery. Movement of your wrist charges a very efficient capacitor which powers the quartz movement. Once the capacitor is fully charged, men models will store energy for 724 days without being worn. Ladies models store energy for 3-7 days. Of course, if the watch is worn every day the capacitor is continually recharged. The watch alerts you to a low capacitor charge when the seconds hand starts to move in two second intervals.

Lap timer: A chronograph function that lets the wearer time segments of a race. At the end of a lap, he stops the timer, which then returns to zero to begin timing the next lap.

Liquid-crystal display (LCD): A digital watch display that shows the time electronically by means of a liquid held in a thin layer between two transparent plates. All LCD watches have quartz movements.

Lugs: Projections on a watch face to which the watch band or bracelet is attached

Luminescence: Luminous dials first appeared during the Great War when soldiers needed to tell the time in the dark. Early forms used Zinc Sulphide compound agitated by a radioactive salt. It was painted on hands and was potentially dangerous to those applying it. Its use was banned in the 50’s, since Tritium, a substance with a low radio activity, replaced it. Other methods have been devised. Timex’s ‘Indiglo’ uses electronic luminescence; a button on the side of the case causes a tiny current from the battery to the electrodes and gives off energy in the form of light. Seiko uses fluorescent material on the dial, activated by any exposure to light.

Manual: A mechanical movement that must be wound by hand to store energy in the spring to keep running.

Markers – Indicators on the face of a watch to mark out time, indicate hours etc.

Measurement conversion: A feature, usually consisting of a graduated scale on the watch’s bezel, that lets the wearer translate one type of measurement into another-miles into kilometres, for instance, or pounds into kilograms

Mechanical movement: A movement powered by a mainspring, working in conjunction with a balance wheel. Most watches today have electronically controlled quartz movements and are powered by a battery. However, mechanical watches are currently enjoying resurgence in pop

ularity.

Minute repeater: A watch which can additionally tell the time, at the push of a button or move of a small slide on the side of the case, by striking the hours, quarter hours and minutes since the last quarter hour on small goings inside the watch. Such complex watches are never inexpensive.

Moonphase display: A graphic display by means of a specially shaped aperture in the dial to indicate the phase of the moon, i.e. full, new or somewhere in between. Very popular in the 90’s but losing favour in the second half of the century.

Movement: The inner mechanism of a watch that keeps time and moves the watch’s hands, calendar, etc. Movements are either mechanical or quartz.

Perpetual Calendar – A highly complicated movement displaying calendar information that adjusts to different lengthen months and years. Perpetual calendars are often among the most valuable, highly sought after watches.

Power reserve indicator: A feature that shows when the watch will soon need a new battery or winding. A battery reserve indicator on a quartz watch informs the wearer when the battery is low. Often this is indicated by the second’s hand moving at two or three-second intervals. Seiko’s Kinetic watches are quartz watches that do not have a battery (see Kinetic). When a Seiko Kinetic needs to be wound, the seconds hand will also move in two second intervals.

Pushers or push pieces: Push buttons are on the case of the chronographs and some complicated watches. Most are used to stop and start a stopwatch but sometimes serve other functions. • PVD -physical vapour deposition: A coating of titanium nitrate applied in a vacuum and then covered by a coating of 22k gold to obtain a gold coloured finish.